diff --git a/lib/SILOptimizer/Utils/SILIsolationInfo.cpp b/lib/SILOptimizer/Utils/SILIsolationInfo.cpp
index 91fc48c5634ca..631dc5c29f742 100644
--- a/lib/SILOptimizer/Utils/SILIsolationInfo.cpp
+++ b/lib/SILOptimizer/Utils/SILIsolationInfo.cpp
@@ -128,8 +128,9 @@ bool DeclRefExprAnalysis::compute(Expr *expr) {
         return Action::Stop();
       }
 
-      if (isa<CoerceExpr, MemberRefExpr, ImplicitConversionExpr, IdentityExpr>(
-              expr)) {
+      // TODO: is this right?
+      if (isa<CoerceExpr, MemberRefExpr, ImplicitConversionExpr, IdentityExpr,
+              LoadExpr, SubscriptExpr, InOutExpr>(expr)) {
         parentAnalysis.lookThroughExprs.push_back(expr);
         return Action::Continue(expr);
       }
diff --git a/test/Concurrency/transfernonsendable_sending_params.swift b/test/Concurrency/transfernonsendable_sending_params.swift
index f8024bc575571..38f3e54bc3f47 100644
--- a/test/Concurrency/transfernonsendable_sending_params.swift
+++ b/test/Concurrency/transfernonsendable_sending_params.swift
@@ -3079,3 +3079,16 @@ func testNonSendableCaptures(ns: NonSendableKlass, a: isolated MyActor) {
     let _ = ns
   }
 }
+
+// https://github.com/swiftlang/swift/issues/84376
+
+@MainActor
+class NonFinalMainActorClass {
+  var nonSendableState: [NonSendableKlass] = []
+
+  func testClassMethodSubscriptLookupPropagatesIsolation() {
+    let alias = nonSendableState[0]
+    transferArg(alias) // expected-warning {{sending 'alias' risks causing data races}}
+    // expected-note @-1 {{main actor-isolated 'alias' is passed as a 'sending' parameter; Uses in callee may race with later main actor-isolated uses}}
+  }
+}